The Gene Expression And Pathogenesis Of Endometrioid Associated Ovarian Cancer

OBJECTIVE:Endometriosis associated ovarian cancer(EAOC)may come from endometriosis by malignant transformation manner.This research aimed to identify the key gene which triggers the malignant transformation of endometriosis to EAOC.We detected the SPEN genes expression in EAOC tumor tissues and ovarian endometrial cancer cell lines,and discussed the regulatory role of SPEN in ovarian endometrial cancer cell proliferation and invasion.METHODS:There is 1 case of patient who underwent surgery in Peking Union Medical College Hospital(PUMCH)obstetrics and gynecology department.The pathology confirmed as ovarian endometrial carcinoma with atypical endometriosis.We presented high throughput DNA sequencing of tumor high frequency mutation gene chip to the paraffin embedded specimens of eutopic endometrium,ovarian ectopic endometrium,ovary atypical endometriosis and ovarian cancer tissues which were obtained by Laser-Capture Microdissection technique.In order to find the differentially expressed genes.Then we concentrated on SPEN gene.The expression of SPEN in different ovarian cancer tissues were analyzed by ovarian cancer tissue microarray combined with immunohistochemistry and different cell lines were analyzed by real-time fluorescence quantitative PCR.In this study,ovarian endometrioid cancer cell lines TOV-112D and IGROV1 were used for further research.SPEN expression was silenced by lentivirus infection technique,and the effects of SPEN gene on cell proliferation,invasion and migration were evaluated by colony formation assay,EdU assay,Transwell migration assay and subcutaneous tumor formation rate in mice.Analyzed the changes of cell biological function after SPEN silencing by high throughput RNA sequencing(RNA-seq)combined with GO and KEGG pathway analysis.We used co-immunoprecipitation combined with mass spectrometry and western blot to detect and verify the expression of downstream proteins of SPEN.RESULT:High throughput DNA sequencing of tumor high frequency mutation gene chip result showed that the 4 specimens of eutopic endometrium,ovarian ectopic endometrium,ovary atypical endometriosis and ovarian cancer tissues have 261 same gene mutations(including BRCA2、EGFR、NF1、CTNN1B、KRAS、BRAF).There were 2 same mutations for ovarian ectopic endometrium,ovary atypical endometriosis and ovarian cancer tissues.20 unique gene mutations were found in only ovarian cancer tissues.The expression of SPEN gene was increased in EAOC cancers(P<0.01).It was also increased in EAOC related cell lines TOV-112D(P=0.014),TOV-21G(P<0.01)and ES-2(P<0.01).Effective silencing of SPEN expression increased tumor cell proliferation,invasion and migration of TOV-112D and IGROV1 cells.After silencing SPEN,we used GO and KEGG analyzed RNA-seq data and found enrichment of Notch signaling pathway,and western blotting confirmed the over expressions of DLL1,JAG1,HES1 and HEY1 proteins.CONCLUSION:.SPEN is highly expressed in EAOC,and the inhibition of SPEN expression can promote the proliferation and metastasis of ovarian endometrioid carcinoma and actives Notch signaling pathway.SPEN may be one of the mechanisms of ovarian endometrioid cancer and a new target for EAOC prevention and treatment.